Performance

· 17 checks — Lighthouse + waterfall + sustainability rolled into one auditable list.

SCORE

GRADE

FIX

REVIEW

PASS

INFO

Performance-focused optimization plan with CWV assessment, top offenders, and time estimates

Mobile Desktop

Performance

Accessibility

100

Best Practices

SEO

First Contentful Paint First Contentful Paint — how long until the browser renders the first piece of content. Under 1.8s is good.

1.96 s

Largest Contentful Paint Largest Contentful Paint — how long until the largest visible element loads. Under 2.5s is good.

5.49 s

Total Blocking Time Total Blocking Time — total time the main thread was blocked, preventing user input. Under 200ms is good.

193 ms

Cumulative Layout Shift Cumulative Layout Shift — measures visual stability. How much the page layout shifts during loading. Under 0.1 is good.

0.000

Speed Index Speed Index — how quickly content is visually displayed during load. Under 3.4s is good.

1.96 s

Time to Interactive Time to Interactive — how long until the page is fully interactive and responds to user input. Under 3.8s is good.

5.71 s

Page Load Progression

375 ms

750 ms

1.1 s

1.5 s

1.9 s

2.2 s

2.6 s

3.0 s

Checks

10 PASS 4 REVIEW 1 FIX

Third-Party Impact

Action

100% third-party, 0 ms blocking

FIX

100% third-party, 0 ms blocking

Third-party code accounts for 100% of page weight (679.1 KiB of 680.4 KiB)

Third-party blocking time is low (0 ms)

100%

First-party Third-party

Image Optimization

23 images, 0 KB saveable

REVIEW

23 images, 0 KB saveable

is missing width/height — may cause layout shift

Set explicit width and height to prevent CLS.

23 images 240 KB

0 oversized -0 KB

12 legacy format

1 missing dimensions CLS risk

Set explicit width and height to prevent CLS.

Why this matters

Performance issues directly impact user engagement and conversion rates.

JS Execution Cost

Action

1683ms total JS execution

REVIEW

1683ms total JS execution

https://www.mediawiki.org/wiki/MediaWiki: 650ms CPU time

https://www.mediawiki.org/w/load.php?lang=en&modul...: 379ms CPU time

Unattributable: 361ms CPU time

https://www.mediawiki.org/w/load.php?lang=en&modul...: 292ms CPU time

Third-party scripts: 1683ms (100% of total)

Main Thread Breakdown

Script Evaluation 37% Style & Layout 26% Other 21% Script Parsing & Compilation 11%

Script	Total	Scripting	Parse/Compile	Party
https://www.mediawiki.org/wiki/MediaWiki	650ms	26ms	5ms	3rd
https://www.mediawiki.org/w/load.php?lang=en&modules=startup&only=scripts&raw=1&skin=minerva	379ms	322ms	10ms	3rd
Unattributable	361ms	8ms	0ms	3rd
https://www.mediawiki.org/w/load.php?lang=en&modules=ext.centralNotice.choiceData%2Cdisplay%2CgeoIP%2CimpressionDiet%2CkvStore%2CstartUp%7Cext.centralauth.centralautologin%7Cext.checkUser.clientHints%7Cext.discussionTools.init%2Cminervaicons%7Cext.echo.centralauth%7Cext.eventLogging%2CnavigationTiming%2CtestKitchen%2CwikimediaEvents%7Cext.eventLogging.metricsPlatform%7Cext.parsermigration.survey%7Cext.urlShortener.toolbar%7Cext.wikimediaEvents.testKitchen%7Cjquery%2Cmoment%2Coojs%2Coojs-ui-core%2Coojs-ui-windows%2Crangefix%2Csite%7Cjquery.client%2CtextSelection%7Cmediawiki.DateFormatter%2CString%2CTitle%2Capi%2Cbase%2Ccldr%2Ccookie%2Cexperiments%2CjqueryMsg%2Clanguage%2Crouter%2Cstorage%2Ctemplate%2Cuser%2Cutil%2CvisibleTimeout%7Cmediawiki.libs.pluralruleparser%7Cmediawiki.page.media%2Cready%7Cmediawiki.page.watch.ajax%7Cmediawiki.template.mustache%7Cmobile.codex.styles%7Cmobile.init%2Cstartup%7Coojs-ui-windows.icons%7Cskins.minerva.scripts%7Cwikibase.databox.fromWikidata&skin=minerva&version=7g2p1	292ms	96ms	185ms	3rd

JS Bundles

6 scripts, 100 KB unused

REVIEW

6 scripts, 100 KB unused

https://www.mediawiki.org/w/load.php?lang=en&modul...: 100 KB unused (51%)

Consider code splitting or tree shaking to reduce unused code.

Total unused JavaScript: 100 KB

100 KB unused JavaScript

Downloaded but never executed on this page.

Script	Size	Unused	Minified	Party
https://www.mediawiki.org/w/load.php?lang=en&modules=ext.centralNotice.choiceData%2Cdisplay%2CgeoIP%2CimpressionDiet%2CkvStore%2CstartUp%7Cext.centralauth.centralautologin%7Cext.checkUser.clientHints%7Cext.discussionTools.init%2Cminervaicons%7Cext.echo.centralauth%7Cext.eventLogging%2CnavigationTiming%2CtestKitchen%2CwikimediaEvents%7Cext.eventLogging.metricsPlatform%7Cext.parsermigration.survey%7Cext.urlShortener.toolbar%7Cext.wikimediaEvents.testKitchen%7Cjquery%2Cmoment%2Coojs%2Coojs-ui-core%2Coojs-ui-windows%2Crangefix%2Csite%7Cjquery.client%2CtextSelection%7Cmediawiki.DateFormatter%2CString%2CTitle%2Capi%2Cbase%2Ccldr%2Ccookie%2Cexperiments%2CjqueryMsg%2Clanguage%2Crouter%2Cstorage%2Ctemplate%2Cuser%2Cutil%2CvisibleTimeout%7Cmediawiki.libs.pluralruleparser%7Cmediawiki.page.media%2Cready%7Cmediawiki.page.watch.ajax%7Cmediawiki.template.mustache%7Cmobile.codex.styles%7Cmobile.init%2Cstartup%7Coojs-ui-windows.icons%7Cskins.minerva.scripts%7Cwikibase.databox.fromWikidata&skin=minerva&version=7g2p1	307 KB	100 KB (51%)	✓	3rd
https://www.mediawiki.org/w/load.php?lang=en&modules=startup&only=scripts&raw=1&skin=minerva	20 KB	—	✓	3rd
https://www.mediawiki.org/w/load.php?lang=en&modules=ext.visualEditor.core.utils.parsing%7Cext.visualEditor.targetLoader%2Ctrack%2Cve&skin=minerva&version=sflfg	9 KB	—	✓	3rd
https://auth.wikimedia.org/metawiki/wiki/Special:CentralAutoLogin/checkLoggedIn?useformat=mobile&wikiid=mediawikiwiki&usesul3=1&type=script	1 KB	—	✓	3rd
https://www.mediawiki.org/w/load.php?lang=en&modules=mediawiki.action.view.postEdit%7Cmediawiki.notification%2CtempUserCreated%7Coojs-ui.styles.icons-interactions&skin=minerva&version=1d7cu	9 KB	—	✓	3rd
https://www.mediawiki.org/w/load.php?lang=en&modules=oojs-ui-widgets%7Coojs-ui-widgets.icons%7Coojs-ui.styles.icons-editing-core&skin=minerva&version=9e91j	20 KB	—	✓	3rd

Consider code splitting or tree shaking to reduce unused code.

Why this matters

This bundle has high unused code — code-split or tree-shake to ship only what executes.

Source: web.dev / Lighthouse coverage

Green Hosting

Action

Whether the site is served from green-energy infrastructure

REVIEW

Green Hosting

No green hosting detected

A+

Page Weight Budget

680 KB transferred, 38 requests

PASS

680 KB transferred, 38 requests

Page weighs 2.1 MB (680 KB transferred)

38 HTTP requests

Estimated 0.14 g CO2 per page load

680 KB transferred

38 requests

0.14 g CO2 per page load

JavaScript 366.6 KiB 54%

Images 240.0 KiB 35%

CSS 33.4 KiB 5%

Other 22.1 KiB 3%

HTML 16.6 KiB 2%

Other 1.7 KiB 0%

0 2.4 MB 4.9 MB

Under budget

A+

Text Compression

All text resources are compressed

PASS

All text resources are compressed

All text resources are properly compressed.

A+

Font Loading

No web fonts (system fonts)

PASS

No web fonts (system fonts)

No web fonts loaded — system fonts are fastest

No web fonts loaded — system fonts are optimal.

A+

Resource Caching

All resources properly cached

PASS

All resources properly cached

No caching issues found

All static resources have appropriate caching headers.

A+

Critical Rendering Path

No render-blocking resources

PASS

No render-blocking resources

No render-blocking resources detected

A+

Resource Hints

3 hints, 0 missing preconnects

PASS

3 hints, 0 missing preconnects

Page uses 3 resource hint(s)

Current Resource Hints

preconnect

preload

—

dns-prefetch

prefetch

—

3 resource hints configured

Page Weight Inventory

38 resources · 680 KB · 100 KB savings available

PASS

38 resources · 680 KB · 100 KB savings available

Within 1MB page-weight target

Got: 680 KB

~100 KB of savings available

37 third-party resources (100% of weight)

2 resources over 200KB

38 resources · 680.4 KiB · 37 third-party Within 1MB page-weight target

JavaScript 54% · 366.6 KiB

Image 38% · 255.8 KiB

CSS 5% · 33.4 KiB

Document 3% · 22.9 KiB

Other 0% · 1.7 KiB

~100.4 KiB of savings available

Remove unused JavaScript: 100.4 KiB

#	Resource	Type	Size	Cache	Unused	3rd party	Issues

38 resources			680.4 KiB

A+

Render-Blocking Resources

No render-blocking resources detected

PASS

No render-blocking resources detected

No render-blocking resources detected in <head>

A+

Third-Party Resources

No third-party resources detected

PASS

No third-party resources detected

HTTP Caching

max-age=2592000 (4 weeks)

PASS

max-age=2592000 (4 weeks)

Cache-Control header is set

Got: max-age=2592000

Effective TTL: 4 weeks (max-age=2592000)

No ETag or Last-Modified header

Conditional requests (304 Not Modified) are not possible without validators.

Cache-Control

max-age=2592000

Directive	Value	Meaning
max-age	2592000	Cache for 4 weeks

Effective TTL: 2592000 seconds

Network Waterfall

38 requests over 464ms

INFO

HTML JavaScript CSS Images Fonts XHR/Fetch Other

Third-Party Script Cost

Per-script blocking time, transfer cost, and cache headers

INFO

100% of JavaScript execution is third-party

First-party Third-party 1683ms · 344KB · $5/mo

Script	Category	Execution	Transfer	Unused	Monthly Cost	Verdict
www.mediawiki.org www.mediawiki.org	Other	650ms	17 KB	—	$2/mo	Costly
www.mediawiki.org www.mediawiki.org	Other	379ms	20 KB	—	$1/mo	Costly
Unattributable Unattributable	Other	361ms	0 KB	—	$1/mo	Costly
www.mediawiki.org www.mediawiki.org	Other	292ms	307 KB	51%	$1/mo	Costly

www.mediawiki.org

Other

Costly

Execution 650ms

Transfer 17 KB

Monthly Cost $2/mo

www.mediawiki.org

Other

Costly

Execution 379ms

Transfer 20 KB

Monthly Cost $1/mo

Unattributable

Other

Costly

Execution 361ms

Transfer 0 KB

Monthly Cost $1/mo

www.mediawiki.org

Other

Costly

Execution 292ms

Transfer 307 KB

Unused 51%

Monthly Cost $1/mo

These scripts may cost more than they're worth

www.mediawiki.org adds 650ms and costs ~$2/month
www.mediawiki.org adds 379ms and costs ~$1/month
Unattributable adds 361ms and costs ~$1/month
www.mediawiki.org adds 292ms and costs ~$1/month

100% of JavaScript execution time is spent on third-party scripts. Consider auditing which scripts are essential.

Why this matters

When third-party JS execution time exceeds your own, performance gains from frontend work are capped by code you don't own.

Learn more ▾

Every millisecond of third-party JS competes with your own for main-thread time. If their share is bigger than yours, optimization on your code base barely moves the needle. Audit, defer, or remove third-parties before further frontend optimization. Use Lighthouse's third-party audit to identify the worst offenders.

Source: web.dev

www.mediawiki.org takes 650ms of CPU time. Consider loading it asynchronously or replacing it with a lighter alternative.

Why this matters

This script has high main-thread execution time — optimize hot paths or defer.

Source: web.dev

www.mediawiki.org takes 379ms of CPU time. Consider loading it asynchronously or replacing it with a lighter alternative.

Why this matters

This script has high main-thread execution time — optimize hot paths or defer.

Source: web.dev

Unattributable takes 361ms of CPU time. Consider loading it asynchronously or replacing it with a lighter alternative.

Why this matters

This script has high main-thread execution time — optimize hot paths or defer.

Source: web.dev

www.mediawiki.org takes 292ms of CPU time. Consider loading it asynchronously or replacing it with a lighter alternative.

Why this matters

This script has high main-thread execution time — optimize hot paths or defer.

Source: web.dev

51% of www.mediawiki.org's code is unused. The script may be loading features you don't use.

Why this matters

Bundle has high unused-code ratio — tree-shaking and route-splitting recover the wasted bytes.

Source: web.dev

How third-party costs are calculated

All checks on this page are automated. Results are estimates - run targeted manual reviews when the score affects a release decision.